SmartFren Wide Replacement Battery 3.7V 1300mAh Li-ion

SmartFren Wide — 3.7V Li-ion 1300mAh Replacement Battery

This is a 3.7V Li-ion cell rated at 1300mAh (4.81Wh), built to replace the original battery in the SmartFren Wide smartphone. The Wide uses a removable battery format, so swapping the cell restores capacity when the original no longer holds charge. Dimensions are 43.50 × 47.00 × 6.10mm — confirm your existing cell matches before installing.

• SmartFren Wide platform fit: The Wide shares a single-cell 3.7V nominal architecture common to budget Android handsets of this generation. The connector pinout and physical footprint are consistent across the Wide range, so one cell covers the variant lineup without adapters or modifications.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a smartphone test rig. The BMS accepted charge at standard rates and held voltage above the low-battery cutoff threshold through full discharge without tripping prematurely.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle. This gives the fuel gauge IC time to map its coulomb counter against the new cell's actual discharge curve before any high-current charging session pushes current into an uncalibrated cell.

Sudden shutdown at 20–30% on the SmartFren Wide after a cell swap

This happens when the fuel gauge IC is still calibrated to the old cell's voltage-versus-capacity curve. Under modem or screen load, current draw spikes and the new cell's voltage drops faster than the IC expects — triggering an emergency shutdown even though the display still shows charge remaining. The phone isn't defective; the gauge just doesn't know what 20% looks like on the new cell yet. Run two full discharge-to-charge cycles without interruption and the shutdowns should stop.

Phone gets warm near the battery during the first few charges

A new Li-ion cell typically has higher internal impedance than a well-cycled one. During the first few charges, the charge IC works harder to push current through that higher resistance, generating more heat than you'd see with the original aged cell. This is normal and reduces after the first two to three cycles as internal impedance drops. If warmth persists beyond three cycles or the case becomes hot to the touch, stop charging and check that the connector is fully seated.